Neighbor’s dog

Just a quick question for those who have more experience with animal behavior. I’m having an issue with neighbors dog defecating on my lawn. The neighbor says he’ll get a leash ( brilliant idea, genius ) to prevent this from continuing, but I’m just curious about something: if I am in my yard when the dog comes along , I chase it off when it tries to do it on my lawn. By doing this, does that mean when I am NOT in my yard the dog is encouraged to use my lawn because the opportunity is there since there is no deterrent or does my “shooing away” the dog occasionally teach it that my lawn is “verboten”? That’s a good question, ain’t it? Because I’m not sure which action by me works better.